How do white cases (and components) fare in the long term?

[Quartz]

As the title says, I'd like to know how white cases and components fare in the long term. Do they discolour as happened with the beige cases of old? How about dirt?

 

[Quartz]

Then again I don't smoke or vape so I've not got that to deal with as that used to be the major discoloration for old cases.

IME the major reason for discoloration was UV light.